1. Field of Invention
The present invention relates to a method of manufacturing an ink jet head used in an ink jet method in which droplets are ejected, and an ink jet head.
2. Description of Related Art
In a related art droplet ejecting method, a given amount of liquid material can be deposited to a desired position. An ink jet method, which is suitable for ejecting an especially small amount of liquid material, is an example of such a method.
An ink jet head used in the ink jet method includes a cavity containing liquid, and a nozzle plate in which nozzles communicating the cavity are formed. The ink jet head, using a nozzle opening at an opposite side of the cavity as an ejection orifice, ejects the liquid contained in the cavity from the ejection orifice.
In such an ink jet head, characteristics of contact with liquid in the vicinity of an ejection orifice of a nozzle especially, namely whether the vicinity of the ejection orifice is lyophobic or lyophilic, is an important factor for stably ejecting droplets composed of the liquid.
From the point of view of related art, an ink jet head in which a surface of a nozzle plate, at a side where the ejection orifice is formed, is treated with eutectoid plating. As such, the surface at the ejection orifice side and the vicinity of the ejection orifice inside a nozzle is lyophobic, as disclosed in Japanese Unexamined Patent Publication No. 4-294145.
Furthermore, as a technique in which attention is focused on whether lyophobic or lyophilic, a technique in which an ink-repellent film (a lyophobic film) is formed on a surface of a nozzle plate at a side the ejection orifice is formed, and, as liquid to be ejected, liquid whose receding dynamic contact angle is 15 degrees or more with respect to the ink-repellent film is used, as disclosed in Japanese Unexamined Patent Publication No. 2000-290556.